In kde4 with task manager set to group programs by name, when you click on a program in the taskbar and it lists above it all the open windows of that program but they don't all fit on the screen, how do you scroll that list? Is there a way to split that list into multiple columns so you don't have to scroll it?

you may need to file a bug/wish on bugs.kde.org

how many windows of a given program are you talking about? I would guess that thats not an issue often seen

It only fits 20 onscreen. I normally have several dozen Chrome windows open. Session Buddy saves my windows and tabs when I close Chrome. The largest session it saved had 62 windows (187 tabs), so I probably don't go much over that.

Is KDE4 still maintained?

I just switched from Windows 7 to KDE on CentOS. I've been using Linux for many years, but this is my first time putting a GUI on it. Can you recommend one that does not have this problem?

Thank you.

sorry but I have no recent experience with other environments, you could ask on their forums which would be quicker than installing and testing but what your doing is a bit unusual/extreme

KDE4 is no longed actively developed and I do not believe 5 is available at this time on Centos but doubt it would address your case

have you looked at Chrome tab extensions like "tab outliner" or "tab organizer" ? seems that there a numerous extensions for tab management

KDE4 is no longer maintained (itr, ie. plasma-desktop)
This is the wring subforum (taskbar => plasma-desktop), but you may want to look into the "present windows" effect (aka "exposé") which can show all windows of one (the current) class.

In theory, a taskbar could also invoke it.

moved to Plasma forum